Nature and Weather in South East England

Put your cursor over any photo on this page to see its caption, or click here to see more April butterfly and insect photos.For more information on butterflies and moths see the Butterfly Conservation website.
Butterflies can be quite abundant on warm days in April. Peacocks, small tortoiseshells, commas and the bright yellow brimstone (the original "butter fly") all overwinter as adults and become active when the sun shines (ideally when the temperature goes above 15 degrees, though this does not seem to be a hard and fast rule).

Small tortoiseshells and peacocks look dark in flight (the colour of their underwings) and you only can see their colourful upperwings when they settle. Both have a convenient habit of basking on paths, from which they fly up when walkers approach. Neither one has been quite as common as it ought to be in recent years, however, with small tortoiseshell numbers particularly reduced. Commas are also fairly elusive at this time of year (they are more abundant when they have their second generation in the summer) but can be found near hedgerows and banks of bramble.

Brimstones are much more frequently seen. The bright yellow males (they are the original "butter fly") hurry past at great speed and almost never seem to rest, but are easy to identify on the wing., When they do stop, they close their wings, so all you can ever photograph is their green (and very well camouflaged) underwings. Females have upperwings that are almost white and paler green underwings, and in flight can easily be mistaken for a large white. But the shape of their wings - or a sight of their underwings - soon settles the argument.

In 2017 (and to a lesser extent 2018) there were also some red admirals to be seen in the first half of the month. These migrant butterflies do not arrive from the continent till May, but some manage to overwinter from the previous year, going into an inactive state known as a diapause in the same way as the peacocks and small tortoiseshells. It is not unheard of to see them on milder days in the winter months, but surviving into spring seems to be a new trend. There is as yet no evidence that they go on to breed, however, especially as the May arrivals are already mated females who are just looking for a place to lay eggs.

Speckled woods can overwinter as pupae or caterpillars and may just be seen in the first half of April, though the second half is a more normal time. They are found in woods and shady places. The three white species commonly known as cabbage whites - the large and small white and the green-veined white - also overwinter as pupae and may be seen from quite early in April, with the small white typically the first to appear and the large white more later in the month. These are very hard species to tell apart because they are even more flighty than other butterflies and very hard to identify until they settle.

If you can find one at rest, the green veins on the underside of its wings are a reliable guide to the green-veined white, while large whites have much larger black tips which extend down the wing edge. On the small white the dark wingtips are smaller and more greyish. Both small and large whites have somewhat yellowy underwings for camouflage purposes and for this reason it is just possible that you might mistake one in flight for a brimstone. As mentioned above, the paler yellow female brimstone can also look like a large white as it flies by.

Perhaps the most lovely April butterfly of all, however, and the only one that is exclusively found at this time of year, is the orange tip. It feeds on garlic mustard and cuckoo flower, and so is particularly in evidence along country lanes in mid to late April when those plants are in bloom. The orange-tipped wings of the male make it easy to identify in flight, while its lower underwing is a mottled olive colour that disguises it perfectly against vegetation. This lower underwing pattern is the only way to identify the female, which does not have an orange tip and otherwise looks remarkably like a small white. She lays one egg per stem on garlic mustard or cuckoo flower, and the caterpillar then eats the plant's seeds and becomes a chrysalis, in which form it remains until the following spring.

You can also see the holly blue, which has a deep blue upperwing and a pale blue underwing with spots. It is the only blue butterfly at this time of year and often can be found circling around and landing on bramble, ivy and holly (on which it lays its eggs). Females have a large black border to their upperwings while males have a very thin one at their wing tip. In flight both can look almost silver.

Last (and probably least) is the dingy skipper, which is a possibility towards the end of April. But this is a very small and nondescript brown butterfly that you could easily mistake for a day-flying moth. It particularly likes downland habitats, but can be found elsewhere.

Other insects

The number of insects increases rapidly in April - they are the reason migrating birds return at this time and chose England to breed in. Bees are particularly in evidence around trees in blossom. You might not immediately see then, but sit below a flowering blackthorn or cherry tree and you can hear a very summery hum. Oilseed rape flowers are another good place.

As well as the honeybee, which live in colonies all winter, you see lots of queen bumble bees at this time of year. These are sole representatives of their species to overwinter and at this time of year they fly around and feed and look for nesting sites. Later - in May - they will become confined to the nest and become machines for turning out young, so you might say that in April they get their little bit of freedom before the hard work begins.

There are various species of bumble bee, some of which - like the common carder bee - look quite different. There are also solitary (ie, non-colony dwelling) bee species that are bumble bee-sized, such as the hairy-footed flower bee (the males golden, the females black), a common early spring species that likes to feed on lungwort and grape hycacinth. Other solitary bees - particularly various types of mining bees (early, grey, yellow-legged...) look more like honeybees. Though less often seen, queen wasps are also out and about on the same mission as the queen bumbles - looking for a nesting site (perhaps in your loft...).

On a warm day the air can also be full of tiny flying insects: you get swarms over rivers or in the air towards dusk. Not all of these are "gnats": Some I managed to photograph in April 2017 were identified by those more expert than me as (tiny) parasitic wasps. There are also a series of species under the umbrella of March flies - tiny little flies that appear in swarms (in early April 2018 I found lots on wood anemone flowers in one wood).

A rather larger member of the March flies group are St Mark's flies, so called because they are supposed to appear around St Mark's Day which is 25 April. The legs of these flies hang down below them, looking rather like a sting, but they are in fact quite harmless. They appear in swarms and are particularly fond of cow parsley and alexanders flowers, on which they can settle in great numbers.

There are also hoverflies right from the start of the month as well as common house flies - but the latter rarely seem to be a nuisance, as they can become later in the summer. In addition, note the intriguing bee fly, which has a fuzzy brown body and likes April blooms such as cuckoo flower and blackthorn.

Ladybirds are also out and about, particularly the seven-spot ladybird, though other species may be seen if you are lucky (for example the tiny twenty four-spot, which I saw in 2018). Native ladybirds emerge as adults in the late summer, feed up and then lay dormant over the winter and emerge in early spring to mate and lay eggs. The invasive foreign harlequin ladybirds breed all summer, which unfortunately gives them an advantage over the indigenous species.

Other insect life is around, but harder to spot. Look down at the flowers of dandelions, lesser celandines or daffodils and you might see tiny bugs crawling about on them that only an expert could identify. Spiders are increasingly active but not very conspicuous. I have also sometimes recorded crane flies in April.